svn commit: r230268 - head/sys/kern

[Alan Cox]

Author: alc
Date: Tue Jan 17 16:20:50 2012
New Revision: 230268
URL: http://svn.freebsd.org/changeset/base/230268

Log:
  Explain why it is safe to unlock the vnode.
  
  Requested by:	kib

Modified:
  head/sys/kern/imgact_elf.c

Modified: head/sys/kern/imgact_elf.c
==============================================================================
--- head/sys/kern/imgact_elf.c	Tue Jan 17 15:20:41 2012	(r230267)
+++ head/sys/kern/imgact_elf.c	Tue Jan 17 16:20:50 2012	(r230268)
@@ -800,6 +800,9 @@ __CONCAT(exec_, __elfN(imgact))(struct i
 	 * than zero.  Consequently, the vnode lock is not needed by vrele().
 	 * However, in cases where the vnode lock is external, such as nullfs,
 	 * v_usecount may become zero.
+	 *
+	 * The VV_TEXT flag prevents modifications to the executable while
+	 * the vnode is unlocked.
 	 */
 	VOP_UNLOCK(imgp->vp, 0);